Scales and Fat Monitors for Clydesdales

Sorry. A bit off topic but since most of us are Clydes seeking emeritus status, I thought it may be relevant.

Has anyone found an accurate digital scale and fat monitor for above 250 lbs? My experience with scales is they seem to be wildly inaccurate depending on how one stands on the scale. I seek consistant and accurate results and short of getting a doctor's balance scale, is there any other scale for us "big" folks?

My spring scale is not very accurate but it is consistent. I would prefer a digital scale/fat monitor ONLY if it works.

We have a Homedics SC-540 from Bed Bath & Beyond (wasn't expensive). I can step off and step on and lean different ways and it gives me the same answer within 0.2 lb for three consecutive tries. Says it has a 400lb capacity and I have used it as I dropped from 280-270. Don't know about the body fat accuracy but I figure if it's going down, it's good!

I've got a Taylor brand item I picked up for ~25 that was supposed to give weight, %body fat and %water.

The weight seems ok, but like any scale I step onto, my weight can vary +/- 5lbs from what seems to be a stable weight throughout the course of the week. Am I really gaining/shedding a 10lb variable water weight?
I get good repeatability stepping on and off 3 times in a row, but the day to day fluctuation is wierd.

And the %fat/water numbers don't even make sense. when I dropped to 225 from 255, fat went up a % and my water #'s seem to be stuck in the 50s with minor variation.

My experience with scales that purport to measure fat percentage is that they are worthless for anything but noting long-term trends. Their reading goes up and down by large amounts day to day and even hour to hour.